Light naphtha stream conversion to higher octane mixtures is an important part of the oil refining process and has been accomplished by a number of different catalysts in the past including such materials as mixtures of fluorosulfonic acid and antimony pentafluoride which are called in the art, "super-acid" catalysts. However, such catalysts have a relatively short life. Now it has been found that by replacing the fluorosulfonic acid by a plurality fluorine-substituted alkanesulfonic acid having a perfluoromethylene group adjacent to the functional group or a perfluoroalkanesulfonic acid, a conversion catalyst of substantially longer life can be obtained which is capable of effecting the usual octane upgrading processes such as alkylation, isomerization and cracking when in contact with hydrocarbons under the appropriate temperature, pressure and concentration conditions.